Merge pull request #598 from nix-community/bats_testing

Switch to bats over pytest

Author: bbenne10

.envrc

@@ -1,5 +1,9 @@
 # shellcheck shell=bash
 strict_env
 source ./direnvrc
-watch_file direnvrc ./*.nix
+
+watch_file direnvrc
+# shellcheck disable=SC2046
+watch_file $(find . -name "*.nix")
+
 use flake

direnvrc

@@ -37,10 +37,10 @@ _nix() {
 }
 
 _require_version() {
-  local cmd=$1 version=$2 required=$3
+  local cmd=$1 raw_version=$2 version=${2%%[^0-9.]*} required=$3
   if ! printf "%s\n" "$required" "$version" | LC_ALL=C sort -c -V 2>/dev/null; then
     _nix_direnv_error \
-      "minimum required $(basename "$cmd") version is $required (installed: $version)"
+      "minimum required $(basename "$cmd") version is $required (installed: $raw_version)"
     return 1
   fi
 }
@@ -52,7 +52,7 @@ _require_cmd_version() {
     return 1
   fi
   version=$($cmd --version)
-  [[ $version =~ ([0-9]+\.[0-9]+\.[0-9]+) ]]
+  [[ $version =~ ([0-9]+\.[0-9]+(\.[0-9]+)?) ]]
   _require_version "$cmd" "${BASH_REMATCH[1]}" "$required"
 }
 

flake.nix

@@ -33,19 +33,18 @@
             self',
             ...
           }:
+          let
+            nix-direnv = pkgs.callPackage ./default.nix { };
+            test_pkgs = pkgs.lib.callPackagesWith pkgs ./tests { inherit nix-direnv; };
+          in
           {
-            packages = {
-              nix-direnv = pkgs.callPackage ./default.nix { };
-              default = config.packages.nix-direnv;
-              test-runner-stable = pkgs.callPackage ./test-runner.nix { nixVersion = "stable"; };
-              test-runner-latest = pkgs.callPackage ./test-runner.nix { nixVersion = "latest"; };
+            packages = test_pkgs // {
+              inherit nix-direnv;
+              default = nix-direnv;
             };
 
             devShells.default = pkgs.callPackage ./shell.nix {
-              packages = [
-                config.treefmt.build.wrapper
-                pkgs.shellcheck
-              ];
+              treefmt = config.treefmt.build.wrapper;
             };
 
             checks =

shell.nix

@@ -1,14 +1,30 @@
 {
   pkgs ? import <nixpkgs> { },
-  packages ? [ ],
+  treefmt ? null,
+  nix-direnv ? (pkgs.callPackage ./default.nix { }),
+  test_pkgs ? (pkgs.lib.callPackagesWith pkgs ./tests { inherit nix-direnv; }),
 }:
-
-with pkgs;
-mkShell {
-  packages = packages ++ [
-    python3.pkgs.pytest
-    python3.pkgs.mypy
-    ruff
-    direnv
-  ];
+let
+  inherit (pkgs) lib;
+in
+pkgs.mkShell {
+  DIRENV_STDLIB = "${test_pkgs.direnv-stdlib}";
+  DIRENVRC = "${nix-direnv}/share/nix-direnv/direnvrc";
+  BATS_LIB_PATH = lib.strings.makeSearchPath "" (
+    with test_pkgs;
+    [
+      bats-support
+      bats-assert
+    ]
+  );
+  packages =
+    (builtins.attrValues {
+      inherit (pkgs)
+        bats
+        direnv
+        shellcheck
+        ;
+    })
+    ++ (builtins.attrValues (lib.attrsets.filterAttrs (name: _val: name != "direnv-stdlib") test_pkgs))
+    ++ lib.optionals (treefmt != null) [ treefmt ];
 }

test-runner.nix

@@ -0,0 +1,54 @@
+{
+  bash,
+  bats,
+  callPackage,
+  coreutils,
+  direnv,
+  fetchurl,
+  findutils,
+  gnugrep,
+  lib,
+  nix-direnv,
+  nixVersions,
+  writeShellScriptBin,
+}:
+let
+  direnv-stdlib = fetchurl {
+    url = "https://raw.githubusercontent.com/direnv/direnv/refs/tags/v2.37.1/stdlib.sh";
+    hash = "sha256-MMM04OXhqS/rRSuv8uh7CD70Z7CaGT63EtL/3LC08qM=";
+  };
+  bats-support = callPackage ./nix/bats-support.nix { };
+  bats-assert = callPackage ./nix/bats-assert.nix { };
+  mkTestRunner =
+    nixVersion:
+    writeShellScriptBin "test-runner-${nixVersion}" ''
+      set -e
+      export PATH=${
+        lib.makeBinPath [
+          bash
+          direnv
+          nixVersions.${nixVersion}
+          coreutils
+          findutils
+          gnugrep
+        ]
+      }
+      export DIRENV_STDLIB=${direnv-stdlib}
+      export DIRENVRC="${nix-direnv}/share/nix-direnv/direnvrc"
+      export BATS_LIB_PATH="${bats-support}:${bats-assert}"
+
+      echo run unittest
+      ${lib.getExe' bats "bats"} -x --verbose-run tests/
+    '';
+  test-runner-stable = mkTestRunner "stable";
+  test-runner-latest = mkTestRunner "latest";
+in
+{
+  inherit
+    bats-support
+    bats-assert
+    direnv-stdlib
+    test-runner-stable
+    test-runner-latest
+    ;
+}

tests/__init__.py

@@ -0,0 +1,23 @@
+{ fetchFromGitHub, stdenv }:
+stdenv.mkDerivation {
+  name = "bats-assert";
+  version = "2.1.0+";
+  src = fetchFromGitHub {
+    owner = "bats-core";
+    repo = "bats-assert";
+    rev = "912a98804efd34f24d5eae1bf97ee622ca770e9"; # master 8/7/2025
+    hash = "sha256-gp52V4mAiT+Lod2rvEMLhi0Y7AdQQTFCHcNgb8JEKXE=";
+  };
+
+  dontBuild = true;
+  installPhase = ''
+
+    # This looks funny
+    # but they mean that you can use bats' built-in `bats_load_library` easily
+    # when setting $BATS_LIB_PATH to the string of the derivation.
+
+    mkdir -p $out/bats-assert;
+    cp -r src $out/bats-assert/
+    cp load.bash $out/bats-assert
+  '';
+}